nomatch -- replacement wiki markup that is displayed, if there's
no match and output style isn't 'count' either

'count' is also recognized without prepended key name. Other non-keyed
parameters are:

locked -- alias for 'locked=True'

visit -- show a list of accounts with last-login information, only
available in table format

name -- forces replacement of maching username with their
corresponding full names, if available; adds a full names column if combined
with 'visit'

email -- append email address to usernames, if available

Requires USER_VIEW permission for output in any format other then 'count'.
A misc placeholder with this statement is presented to unprivileged users.

Related issues

#6616 Invalid entries for usernames in table - originally wontfix, moved over from UserStatsMacro#9852 Embed some user information in TracWiki - initial and primary development ticket

Development notes

Because I favor added-value over rather uncontrolled growth of Trac plugins I aim at integration of related plugins, addressing their outstanding issues too. See #9852 for more reasons, why I think this is especially a good idea in this case.

Added value

UserQuery uses the existing i18n support in AccountManager to provide i.e. localized messages and table headers - one more
reason for translators to contribute to AccountManagerPlugin.

Translation

Note: I'm halting further implementation of statistics at least temporarily now. TracStatsPlugin does a fairly good job at that already. I'd rather aim at implementing WikiMacros over there then re-inventing the wheel here.